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<div class="titlepage"><div><div><h4 class="title">
<a name="range.reference.utilities.iterator_range"></a><a class="link" href="iterator_range.html" title="Class iterator_range">Class <code class="computeroutput"><span class="identifier">iterator_range</span></code></a>
</h4></div></div></div>
<p>
          The intention of the <code class="computeroutput"><span class="identifier">iterator_range</span></code>
          class is to encapsulate two iterators so they fulfill the <a class="link" href="../../concepts/forward_range.html" title="Forward Range">Forward
          Range</a> concept. A few other functions are also provided for convenience.
        </p>
<p>
          If the template argument is not a model of <a href="../../../../../../../libs/iterator/doc/new-iter-concepts.html#forward-traversal-iterators-lib-forward-traversal-iterators" target="_top">Forward
          Traversal Iterator</a>, one can still use a subset of the interface.
          In particular, <code class="computeroutput"><span class="identifier">size</span><span class="special">()</span></code>
          requires Random Access Traversal Iterators whereas <code class="computeroutput"><span class="identifier">empty</span><span class="special">()</span></code> only requires Single Pass Iterators.
        </p>
<p>
          Recall that many default constructed iterators are <span class="bold"><strong><span class="emphasis"><em>singular</em></span></strong></span>
          and hence can only be assigned, but not compared or incremented or anything.
          However, if one creates a default constructed <code class="computeroutput"><span class="identifier">iterator_range</span></code>,
          then one can still call all its member functions. This design decision
          avoids the <code class="computeroutput"><span class="identifier">iterator_range</span></code>
          imposing limitations upon ranges of iterators that are not singular. Any
          singularity limitation is simply propagated from the underlying iterator
          type.
        </p>
<h5>
<a name="range.reference.utilities.iterator_range.h0"></a>
          <span class="phrase"><a name="range.reference.utilities.iterator_range.synopsis"></a></span><a class="link" href="iterator_range.html#range.reference.utilities.iterator_range.synopsis">Synopsis</a>
        </h5>
<p>
          The core functionality is in the header file <code class="computeroutput"><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">range</span><span class="special">/</span><span class="identifier">iterator_range_core</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
          this includes all of the functionality except the <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">hash_value</span></code>
          and <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">iostream</span></code> support.
        </p>
<p>
          The <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">iostream</span></code> support is in the header <code class="computeroutput"><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">range</span><span class="special">/</span><span class="identifier">iterator_core</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code> while the <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">hash_value</span></code>
          support is in <code class="computeroutput"><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">range</span><span class="special">/</span><span class="identifier">iterator_range_hash</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
        </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span>
<span class="special">{</span>
    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span> <span class="special">&gt;</span>
    <span class="keyword">class</span> <span class="identifier">iterator_range</span>
    <span class="special">{</span>
    <span class="keyword">public</span><span class="special">:</span> <span class="comment">// Forward Range types</span>
        <span class="keyword">typedef</span> <span class="identifier">ForwardTraversalIterator</span>   <span class="identifier">iterator</span><span class="special">;</span>
        <span class="keyword">typedef</span> <span class="identifier">ForwardTraversalIterator</span>   <span class="identifier">const_iterator</span><span class="special">;</span>
        <span class="keyword">typedef</span> <span class="identifier">iterator_difference</span><span class="special">&lt;</span><span class="identifier">iterator</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">difference_type</span><span class="special">;</span>

    <span class="keyword">public</span><span class="special">:</span> <span class="comment">// construction, assignment</span>
        <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator2</span> <span class="special">&gt;</span>
        <span class="identifier">iterator_range</span><span class="special">(</span> <span class="identifier">ForwardTraversalIterator2</span> <span class="identifier">Begin</span><span class="special">,</span> <span class="identifier">ForwardTraversalIterator2</span> <span class="identifier">End</span> <span class="special">);</span>

        <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
        <span class="identifier">iterator_range</span><span class="special">(</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

        <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
        <span class="identifier">iterator_range</span><span class="special">(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

        <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
        <span class="identifier">iterator_range</span><span class="special">&amp;</span> <span class="keyword">operator</span><span class="special">=(</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

        <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
        <span class="identifier">iterator_range</span><span class="special">&amp;</span> <span class="keyword">operator</span><span class="special">=(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">public</span><span class="special">:</span> <span class="comment">// Forward Range functions</span>
        <span class="identifier">iterator</span>  <span class="identifier">begin</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
        <span class="identifier">iterator</span>  <span class="identifier">end</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>

    <span class="keyword">public</span><span class="special">:</span> <span class="comment">// convenience</span>
        <span class="keyword">operator</span>    <span class="identifier">unspecified_bool_type</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
        <span class="keyword">bool</span>        <span class="identifier">equal</span><span class="special">(</span> <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&amp;</span> <span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
        <span class="identifier">value_type</span><span class="special">&amp;</span> <span class="identifier">front</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
        <span class="keyword">void</span>        <span class="identifier">drop_front</span><span class="special">();</span>
        <span class="keyword">void</span>        <span class="identifier">drop_front</span><span class="special">(</span><span class="identifier">difference_type</span> <span class="identifier">n</span><span class="special">);</span>
        <span class="keyword">bool</span>      <span class="identifier">empty</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>

        <span class="identifier">iterator_range</span><span class="special">&amp;</span> <span class="identifier">advance_begin</span><span class="special">(</span><span class="identifier">difference_type</span> <span class="identifier">n</span><span class="special">);</span>
        <span class="identifier">iterator_range</span><span class="special">&amp;</span> <span class="identifier">advance_end</span><span class="special">(</span><span class="identifier">difference_type</span> <span class="identifier">n</span><span class="special">);</span>

        <span class="comment">// for Bidirectional:</span>
        <span class="identifier">value_type</span><span class="special">&amp;</span> <span class="identifier">back</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
        <span class="keyword">void</span> <span class="identifier">drop_back</span><span class="special">();</span>
        <span class="keyword">void</span> <span class="identifier">drop_back</span><span class="special">(</span><span class="identifier">difference_type</span> <span class="identifier">n</span><span class="special">);</span>
        <span class="comment">// for Random Access only:</span>
        <span class="identifier">reference</span> <span class="keyword">operator</span><span class="special">[](</span> <span class="identifier">difference_type</span> <span class="identifier">at</span> <span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
        <span class="identifier">value_type</span> <span class="keyword">operator</span><span class="special">()(</span> <span class="identifier">difference_type</span> <span class="identifier">at</span> <span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
        <span class="identifier">size_type</span> <span class="identifier">size</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
    <span class="special">};</span>

    <span class="comment">// stream output</span>
    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Traits</span> <span class="special">&gt;</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">,</span><span class="identifier">Traits</span><span class="special">&gt;&amp;</span>
    <span class="keyword">operator</span><span class="special">&lt;&lt;(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">,</span><span class="identifier">Traits</span><span class="special">&gt;&amp;</span> <span class="identifier">Os</span><span class="special">,</span>
                <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="comment">// comparison</span>
    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator2</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">==(</span> <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                     <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator2</span><span class="special">&gt;&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">==(</span> <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                     <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">==(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                     <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator2</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">!=(</span> <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                     <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator2</span><span class="special">&gt;&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">!=(</span> <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                     <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">!=(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                     <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator2</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">&lt;(</span> <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                    <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator2</span><span class="special">&gt;&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">&lt;(</span> <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                    <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">&lt;(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">l</span><span class="special">,</span>
                    <span class="keyword">const</span> <span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">ForwardTraversalIterator</span><span class="special">&gt;&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="comment">// external construction</span>
    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span> <span class="special">&gt;</span>
    <span class="identifier">iterator_range</span><span class="special">&lt;</span> <span class="identifier">ForwardTraversalIterator</span> <span class="special">&gt;</span>
    <span class="identifier">make_iterator_range</span><span class="special">(</span> <span class="identifier">ForwardTraversalIterator</span> <span class="identifier">Begin</span><span class="special">,</span>
                         <span class="identifier">ForwardTraversalIterator</span> <span class="identifier">End</span> <span class="special">);</span>

    <span class="comment">// Make an iterator_range [first, boost::next(first, n) )</span>
    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardTraversalIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Integer</span> <span class="special">&gt;</span>
    <span class="identifier">iterator_range</span><span class="special">&lt;</span> <span class="identifier">ForwardTraversalIterator</span> <span class="special">&gt;</span>
    <span class="identifier">make_iterator_range_n</span><span class="special">(</span> <span class="identifier">ForwardTraversalIterator</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">Integer</span> <span class="identifier">n</span> <span class="special">);</span>


    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="identifier">iterator_range</span><span class="special">&lt;</span> <span class="keyword">typename</span> <span class="identifier">range_iterator</span><span class="special">&lt;</span><span class="identifier">ForwardRange</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="special">&gt;</span>
    <span class="identifier">make_iterator_range</span><span class="special">(</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="identifier">iterator_range</span><span class="special">&lt;</span> <span class="keyword">typename</span> <span class="identifier">range_iterator</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="special">&gt;</span>
    <span class="identifier">make_iterator_range</span><span class="special">(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">Range</span> <span class="special">&gt;</span>
    <span class="identifier">iterator_range</span><span class="special">&lt;</span> <span class="keyword">typename</span> <span class="identifier">range_iterator</span><span class="special">&lt;</span><span class="identifier">Range</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="special">&gt;</span>
    <span class="identifier">make_iterator_range</span><span class="special">(</span> <span class="identifier">Range</span><span class="special">&amp;</span> <span class="identifier">r</span><span class="special">,</span>
                         <span class="keyword">typename</span> <span class="identifier">range_difference</span><span class="special">&lt;</span><span class="identifier">Range</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">advance_begin</span><span class="special">,</span>
                         <span class="keyword">typename</span> <span class="identifier">range_difference</span><span class="special">&lt;</span><span class="identifier">Range</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">advance_end</span> <span class="special">);</span>

    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">Range</span> <span class="special">&gt;</span>
    <span class="identifier">iterator_range</span><span class="special">&lt;</span> <span class="keyword">typename</span> <span class="identifier">range_iterator</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="identifier">Range</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="special">&gt;</span>
    <span class="identifier">make_iterator_range</span><span class="special">(</span> <span class="keyword">const</span> <span class="identifier">Range</span><span class="special">&amp;</span> <span class="identifier">r</span><span class="special">,</span>
                         <span class="keyword">typename</span> <span class="identifier">range_difference</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="identifier">Range</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">advance_begin</span><span class="special">,</span>
                         <span class="keyword">typename</span> <span class="identifier">range_difference</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="identifier">Range</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">advance_end</span> <span class="special">);</span>

    <span class="comment">// convenience</span>
    <span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">Sequence</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ForwardRange</span> <span class="special">&gt;</span>
    <span class="identifier">Sequence</span> <span class="identifier">copy_range</span><span class="special">(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span>

<span class="special">}</span> <span class="comment">// namespace 'boost'</span>
</pre>
<p>
        </p>
<p>
          If an instance of <code class="computeroutput"><span class="identifier">iterator_range</span></code>
          is constructed by a client with two iterators, the client must ensure that
          the two iterators delimit a valid closed-open range [begin,end).
        </p>
<p>
          It is worth noticing that the templated constructors and assignment operators
          allow conversion from <code class="computeroutput"><span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">iterator</span><span class="special">&gt;</span></code> to <code class="computeroutput"><span class="identifier">iterator_range</span><span class="special">&lt;</span><span class="identifier">const_iterator</span><span class="special">&gt;</span></code>. Similarly, since the comparison operators
          have two template arguments, we can compare ranges whenever the iterators
          are comparable; for example when we are dealing with const and non-const
          iterators from the same container.
        </p>
<h5>
<a name="range.reference.utilities.iterator_range.h1"></a>
          <span class="phrase"><a name="range.reference.utilities.iterator_range.details_member_functions"></a></span><a class="link" href="iterator_range.html#range.reference.utilities.iterator_range.details_member_functions">Details
          member functions</a>
        </h5>
<p>
          <code class="computeroutput"><span class="keyword">operator</span> <span class="identifier">unspecified_bool_type</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span></code>
        </p>
<div class="blockquote"><blockquote class="blockquote"><p>
            <span class="emphasis"><em><span class="bold"><strong>Returns</strong></span></em></span> <code class="computeroutput"><span class="special">!</span><span class="identifier">empty</span><span class="special">();</span></code>
          </p></blockquote></div>
<p>
          <code class="computeroutput"><span class="keyword">bool</span> <span class="identifier">equal</span><span class="special">(</span> <span class="identifier">iterator_range</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></code>
        </p>
<div class="blockquote"><blockquote class="blockquote"><p>
            <span class="emphasis"><em><span class="bold"><strong>Returns</strong></span></em></span> <code class="computeroutput"><span class="identifier">begin</span><span class="special">()</span> <span class="special">==</span> <span class="identifier">r</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()</span> <span class="special">&amp;&amp;</span>
            <span class="identifier">end</span><span class="special">()</span>
            <span class="special">==</span> <span class="identifier">r</span><span class="special">.</span><span class="identifier">end</span><span class="special">();</span></code>
          </p></blockquote></div>
<h5>
<a name="range.reference.utilities.iterator_range.h2"></a>
          <span class="phrase"><a name="range.reference.utilities.iterator_range.details_functions"></a></span><a class="link" href="iterator_range.html#range.reference.utilities.iterator_range.details_functions">Details
          functions</a>
        </h5>
<p>
          <code class="computeroutput"><span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">==(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange1</span><span class="special">&amp;</span>
          <span class="identifier">l</span><span class="special">,</span>
          <span class="keyword">const</span> <span class="identifier">ForwardRange2</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span></code>
        </p>
<div class="blockquote"><blockquote class="blockquote"><p>
            <span class="emphasis"><em><span class="bold"><strong>Returns</strong></span></em></span> <code class="computeroutput"><span class="identifier">size</span><span class="special">(</span><span class="identifier">l</span><span class="special">)</span> <span class="special">!=</span> <span class="identifier">size</span><span class="special">(</span><span class="identifier">r</span><span class="special">)</span> <span class="special">?</span> <span class="keyword">false</span>
            <span class="special">:</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">equal</span><span class="special">(</span> <span class="identifier">begin</span><span class="special">(</span><span class="identifier">l</span><span class="special">),</span> <span class="identifier">end</span><span class="special">(</span><span class="identifier">l</span><span class="special">),</span> <span class="identifier">begin</span><span class="special">(</span><span class="identifier">r</span><span class="special">)</span> <span class="special">);</span></code>
          </p></blockquote></div>
<p>
          <code class="computeroutput"><span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">!=(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange1</span><span class="special">&amp;</span>
          <span class="identifier">l</span><span class="special">,</span>
          <span class="keyword">const</span> <span class="identifier">ForwardRange2</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span></code>
        </p>
<div class="blockquote"><blockquote class="blockquote"><p>
            <span class="emphasis"><em><span class="bold"><strong>Returns</strong></span></em></span> <code class="computeroutput"><span class="special">!(</span> <span class="identifier">l</span> <span class="special">==</span> <span class="identifier">r</span> <span class="special">);</span></code>
          </p></blockquote></div>
<p>
          <code class="computeroutput"><span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">&lt;(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange1</span><span class="special">&amp;</span>
          <span class="identifier">l</span><span class="special">,</span>
          <span class="keyword">const</span> <span class="identifier">ForwardRange2</span><span class="special">&amp;</span> <span class="identifier">r</span> <span class="special">);</span></code>
        </p>
<div class="blockquote"><blockquote class="blockquote"><p>
            <span class="emphasis"><em><span class="bold"><strong>Returns</strong></span></em></span> <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">lexicographical_compare</span><span class="special">(</span>
            <span class="identifier">begin</span><span class="special">(</span><span class="identifier">l</span><span class="special">),</span> <span class="identifier">end</span><span class="special">(</span><span class="identifier">l</span><span class="special">),</span> <span class="identifier">begin</span><span class="special">(</span><span class="identifier">r</span><span class="special">),</span> <span class="identifier">end</span><span class="special">(</span><span class="identifier">r</span><span class="special">)</span> <span class="special">);</span></code>
          </p></blockquote></div>
<p>
</p>
<pre class="programlisting"><span class="identifier">iterator_range</span> <span class="identifier">make_iterator_range</span><span class="special">(</span> <span class="identifier">Range</span><span class="special">&amp;</span> <span class="identifier">r</span><span class="special">,</span>
                                    <span class="keyword">typename</span> <span class="identifier">range_difference</span><span class="special">&lt;</span><span class="identifier">Range</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">advance_begin</span><span class="special">,</span>
                                    <span class="keyword">typename</span> <span class="identifier">range_difference</span><span class="special">&lt;</span><span class="identifier">Range</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">advance_end</span> <span class="special">);</span>
</pre>
<p>
        </p>
<div class="blockquote"><blockquote class="blockquote"><p>
            <span class="emphasis"><em><span class="bold"><strong>Effects:</strong></span></em></span>
          </p></blockquote></div>
<p>
</p>
<pre class="programlisting"><span class="identifier">iterator</span> <span class="identifier">new_begin</span> <span class="special">=</span> <span class="identifier">begin</span><span class="special">(</span> <span class="identifier">r</span> <span class="special">),</span>
<span class="identifier">iterator</span> <span class="identifier">new_end</span>   <span class="special">=</span> <span class="identifier">end</span><span class="special">(</span> <span class="identifier">r</span> <span class="special">);</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">advance</span><span class="special">(</span> <span class="identifier">new_begin</span><span class="special">,</span> <span class="identifier">advance_begin</span> <span class="special">);</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">advance</span><span class="special">(</span> <span class="identifier">new_end</span><span class="special">,</span> <span class="identifier">advance_end</span> <span class="special">);</span>
<span class="keyword">return</span> <span class="identifier">make_iterator_range</span><span class="special">(</span> <span class="identifier">new_begin</span><span class="special">,</span> <span class="identifier">new_end</span> <span class="special">);</span>
</pre>
<p>
        </p>
<p>
          <code class="computeroutput"><span class="identifier">Sequence</span> <span class="identifier">copy_range</span><span class="special">(</span> <span class="keyword">const</span> <span class="identifier">ForwardRange</span><span class="special">&amp;</span>
          <span class="identifier">r</span> <span class="special">);</span></code>
        </p>
<div class="blockquote"><blockquote class="blockquote"><p>
            <span class="emphasis"><em><span class="bold"><strong>Returns</strong></span></em></span> <code class="computeroutput"><span class="identifier">Sequence</span><span class="special">(</span>
            <span class="identifier">begin</span><span class="special">(</span><span class="identifier">r</span><span class="special">),</span> <span class="identifier">end</span><span class="special">(</span><span class="identifier">r</span><span class="special">)</span> <span class="special">);</span></code>
          </p></blockquote></div>
</div>
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<td align="right"><div class="copyright-footer">Copyright © 2003-2010 Thorsten Ottosen,
      Neil Groves<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
</div></td>
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